1. Field of the Invention
The present invention relates to a technical field of a nozzle structure in a washer fluid injection apparatus which supplies a washer fluid to a windshield of a vehicle.
2. Description of the Related Art
In general, a washer fluid supplying apparatus is provided in the vicinity of a window surface, for example, in the vicinity of a windshield of a vehicle, and a structure is made such that a soil on the windshield is washed by injection of the washer fluid onto the windshield as occasion demands and a wiping operation by a wiper blade. In this structure, various kinds of proposals have been conventionally made with respect to a shape of the injection nozzle for improving a washing efficiency. As this kind of nozzle, there has been suggested a diffusion type nozzle in which an injection port of the washer fluid is formed in a long rectangular shape in a lateral direction. In this structure, the washer fluid is applied to a wide range of the window surface and it is possible to efficiently wipe and wash the windshield by the wiper blade even with a little fluid amount. However, in the injection by this diffusion type nozzle, a grain diameter of the washer fluid becomes smaller as the washer fluid is apart from a nozzle center (corresponding to a preset injection hitting point). Further, in this case, the range in which the washer fluid is applied to the window surface is previously set so as to be optimum in a stopping state of the vehicle. Accordingly, in the case of injecting the washer fluid while the vehicle travels, the application range of the washer fluid tends to be lower than the preset range. Further, in the case that the washer fluid is injected in the diffusion shape, a distribution of the grain diameter of the washer fluid is uniform in a vertical direction, as shown in FIG. 6A and a washer fluid drop of a smaller grain diameter which has been injected to an outer periphery side (an outer side portion) of the fluid application range is largely affected by an air flow and furthermore, the influence of the air flow becomes more remarkable as a traveling speed of the vehicle becomes higher. Accordingly, on the basis of the actual case mentioned above, it is possible to set the fluid application range previously taking into consideration the air flow at a time when the vehicle travels, however, in this structure, the fluid application range at the stopping time is displaced to the high position, which is inappropriate position. As a result, it is unavoidable to set the fluid application range to a middle fluid application range between one at the stopping time and one at the traveling time, and there is a problem that the optimum fluid application range can be obtained in neither at the stopping time nor at the traveling time.
Accordingly, in conventional, as shown in Japanese Patent Application Laid-Open (JP-A) No. 2000-52939, there is proposed a structure in which a protruding amount of lip portions respectively formed in a protruding manner in upper and lower edge portions of an injection port for the purpose of regulating an injection range of the washer fluid is set so that the lip portion in the lower side is shorter than the lip portion in the upper side, thereby regulating the injection of the washer fluid in such a manner as to prevent the injection of the washer fluid to the upper side from becoming far from a center of the nozzle, so that the air flow at the vehicle traveling time is hard to affect the washer fluid.
In this case, in the conventional structure mentioned above, the lip portion in the upper side is protruded in comparison with the lip portion in the lower side, however, since the nozzle itself is a small member, the protruding lip portion in the upper side is easily affected by an external world. Namely, there is a problem that a sense of unity in design is reduced at a time when the nozzle is assembled in a nozzle body, and a problem to be solved by the present invention exists here.
Further, the conventional nozzle body mentioned above is formed by machining of a metal material, and is expensive in view of cost. Then, it is proposed that the nozzle is formed by a resin material, however, in the case that the nozzle having the different protruding lengths between the upper and lower lip portions as described above, it is supposed that a force applied from the external world tends to be concentrated in the protruding upper lip portion, so that it is impossible to employ the structure having this shape, and a problem to be solved also exists here.